Endometrial cancer is the second most common cancer among female cancer survivors in the United States. There are an estimated 600,000 endometrial cancer survivors today. Additionally, 49,560 incident endometrial cancer cases are diagnosed each year. Endometrial cancer has been identified by the NCI as an understudied cancer site and late effects research on endometrial cancer patients is very limited to our knowledge. Late effects are of concern among cancer patients due to the toxic effects of chemotherapy and radiotherapy. Specific late effects of concern include second primary cancers, osteoporosis, cardio-toxicity, neuro-toxicity, cognitive deficits, depression, chronic fatigue, chronic pain, infertility and sexual dysfunction. The Utah Population Database (UPDB) provides a unique and excellent resource for epidemiologic research, and links data from the Utah Cancer Registry, hospital electronic medical records, Medicare, driver licenses, voter registration, family history records, and birth certificates. We have successfully completed a study of late effects of 1,001 testicular cancer patients with the same study design (93.2% successfully followed up through the EMR). Within the UPDB linked data with the Utah Cancer Registry, we propose to construct a population- based endometrial cancer patient cohort covering the state of Utah. Our specific aims are: (1) To assemble a population-based cohort of 3,400 endometrial cancer patients and 17,000 age-matched cancer-free women for a comparison group, to investigate the incidence of long-term health effects due to endometrial cancer treatment, (2) To assess the feasibility of administering questionnaires to assess lifestyle factors in a sample of the endometrial cancer survivors (n=500) and cancer-free women for a comparison group (n=500), (3) To determine the feasibility of collecting detailed cancer treatment information such as chemotherapy agents from medical records by conducting medical record abstraction among a sample of endometrial cancer patients (n=200), (4) To compare the quality of information obtained from the existing records and the self-report from the questionnaire on late effects, comorbidities, and cancer treatment (n=1,000). The aim 1 late effects analysis is based on existing data (linkage of cancer registry and EMR) and we are able to obtain late effects information on >90% of cancer patients in Utah. Our project addresses the priority research areas highlighted by the NCI: assessment of late effects, study of survivors with comorbidities, and focusing on an understudied cancer. We will assemble an unprecedented high-quality population-based cohort of 3,400 endometrial cancer patients to study late effects for the first time, at a very low cost due to existing linked databases within te UPDB. This application will also lay important foundation work for a future large-scale population-based endometrial cancer survivorship project. Understanding the long-term effects of cancer treatment and their determinants will be extremely valuable for the 600,000 endometrial cancer survivors and the 49,560 women who will be diagnosed this year.